Method for etching dental porcelain
Abstract
Abstract The method of etching a porcelain dental appliance insitu including the steps of contacting the porcelain with a buffered solution containing trace amounts of hydrogen fluoride and removing the solution after sufficient time has elapsed to etch the porcelain. Preferred solutions are buffered at a pH from about 2.0 to about 6.0 and most preferably from about 3.5 to about 4.5. Contact time of the solution with porcelain ranges from about five minutes to from about five to about thirty minutes or longer. The solution preferably contains an alkali metal fluoride dissolved in a weak acid. In a preferred embodiment, the solution contains about one to about three parts by weight of sodium fluoride dissolved in about 50 parts to about 150 parts by weight of dilute weak acid. The weak acid has a molarity of from about 0.05 molar to about 0.5 molar. The weak acid solution is buffered, if necessary, and has a pH of from about 2.0 to about 6.0 and preferably from about 3.5 to about 4.5 A gelling agent may be added to gel the solution to permit more effective contact of the solution against with the porcelain being treated.
Inventors
- 👤 Peter P. L. Cheung
Bibliographic Details
Claims Analysis
Total Claims: 12References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1986-03-14 | 1986-09-13 | 1987-03-15 | $2000.00 | Window Closed / Lapsed |
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